Magnetic resonance tomography (MRT) or magnetic resonance imaging (MRI) is an imaging method used in medical diagnostics for representing the structure and function of tissues and/or organs in an examination object, e.g., a body of a human or animal patient. To this end, rapidly switching gradient fields generated by a gradient system of the magnetic resonance device may overlay a static basic magnetic field in a magnetic resonance device. Furthermore, a radio frequency antenna unit of the magnetic resonance device serves to radiate RF pulses into the examination object in order to trigger magnetic resonance signals and to receive the triggered magnetic resonance signals. Magnetic resonance images, or in brief images, are produced on this basis.
MRT in particular allows for the generation of time-resolved images of cyclical movements, such as are performed for instance by a heart of a patient. For this purpose, spatial magnetization patterns, (also referred to as tagging patterns), may be impressed onto the examination object with selective RF pulses, (also referred to as tagging pulses or magnetization pulses). With such methods, (also known as tagging methods), the examination object appears with a line or grid pattern in the MR image.
The tagging method was previously implemented in segmented CINE measurements, in order to obtain local movement information, e.g., of a heart. In this way, a number of magnetic resonance images per heart cycle are recorded thereby producing a type of film of the heart movement. With a segmented measurement, the data recording for an MR image is divided into several movement cycles and the magnetic resonance data is only recorded in comparable movement phases.
Moreover, account is taken of the breathing and heart movement during the heart imaging, wherein the movement may be minimized using a breath-hold technique. Due to requirements in terms of spatial and temporal resolution, often only one cycle period, (e.g., only one heartbeat), could previously be triggered, particularly within a typical breath-hold time.